The BGS Lexicon of Named Rock Units — Result Details

Auchmeddon Gravel Member

Computer Code: AMNGR Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Gravel. Interpreted as glaciofluvial outwash. Grey, pebble to boulder grade. Clast-supported with a medium to coarse quartzose sand matrix. Clasts are subrounded to rounded and composed mainly of quartzite (probably reworked from underlying gravel deposits and Devonian conglomerates) - other lithologies are rare. The gravels are crudely horizontally bedded with local sand interbeds displaying horizontal stratification. Clast imbrication measurements indicates palaeocurrents flowing towards the south.
Definition of Lower Boundary: The lower boundary of the formation is a scoured, undulatory erosion surface (amplitude about 1.0m) on reddish brown diamicton of the Byth Till Formation.
Definition of Upper Boundary: The formation either occurs at the present ground surface or is overlain by Holocene peat or alluvial sediments.
Thickness: To 3m
Geographical Limits: Buchan, northeast Scotland. The member is only known from the vicinity of the Howe of Byth Quarry on Sheet 97 (Fraserburgh).
Parent Unit: Blackhills Sand and Gravel Formation (BLSG)
Previous Name(s): Glacial Meltwater Deposits (-4430)
Auchmeddon Member (-3166)
Auchmeddon Gravel (-1948)
Auchmeddon Gravel Formation (-1949)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  North face (as at May 2002) of Howe of Byth Quarry, 18km southwest of Fraserburgh, Buchan, northeast Scotland. Hall et al. 1995. 
Reference(s):
Merritt, J W, Auton, C A, Connell, E R, Hall, A M and Peacock, J D. 2003. The Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, Sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland) 
Connell, E R. 2002. Stratigraphical investigations at three key Quaternary sites in northeast Scotland. Quaternary Newsletter, 98, 29-32. 
Duller, G A T, Wintle, A F and Hall, A M. 1995. Luminescence dating and its application to key-pre-Late Devensian sites in Scotland. Quaternary Science Reviews, Vol.14, 495-519. 
Hall, A M, Duller G A T, Jarvis, J and Wintle, A G. 1995. Middle Devensian ice-proximal gravels at Howe of Byth, Grampian Region. Scottish Journal of Geology, Vol.31, 61-64. 
Merritt, J W, Connell, E R and Bridgland, D R (editors). 2000. The Quaternary of the Banffshire Coast and Buchan; Field Guide. (London: Quaternary Research Association.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable